Tenprint card input device, tenprint card input method and storage medium

ABSTRACT

A fingerprint image processing device includes a memory, and a processor coupled to the memory. The processor performs operations, including reading a tenprint card image which includes a plurality of fingerprint patterns and at least one ruled line to separate one fingerprint imprint area from another fingerprint imprint area, and extracting from the tenprint card image a fingerprint image which includes a part of a fingerprint imprint area and apart of a next fingerprint imprint area.

The present application is a Continuation application of U.S. patentapplication Ser. No. 14/112,922, filed on Oct. 19, 2013, which is basedon International Application No. PCT/JP2012/060359, filed on Apr. 17,2012, which is based on Japanese Patent Application No. 2011-094029,filed on Apr. 20, 2011, the entire contents of which are incorporatedherein by reference.

TECHNICAL FIELD

The present invention relates to a tenprint card input device whichcreates a digital image of a tenprint card for inputting.

BACKGROUND ART

Generally, since a fingerprint composed of many ridges with stripedpattern has two important characteristics of “permanence” and“uniqueness”, it has been used for a person authentication method for along time. Particularly, matching by using fingerprints left on thecrime scene is an effective investigation method.

Recently, in many police agencies, a fingerprint matching system using acomputer (a computing machine) has been introduced, and left fingerprintmatching has been performed. As objects of the left fingerprintmatching, a database of tenprint cards taken from criminals (suspectsand arrestees) has been made.

Ten fingers are 10 fingers of both hands. The 5 fingers of the singlehand are called a thumb finger, an index finger, a middle finger, a ringfinger and a little finger.

As described in a non-patent literature 1 of “The Science ofFingerprints”, the tenprint card includes a total of fourteen kinds ofimages (14 images) containing ten kinds of rolled prints and four kindsof plane prints or slap prints.

Here, it is assumed that, in the tenprint card, ten kinds of rolledprint image frames (ruled line frame) and four kinds of slap print imageframes (ruled line frame) are already printed.

The rolled print images are fingerprints of a thumb finger, an indexfinger, a middle finger, a ring finger and a little finger of both handsindividually imprinted while these fingers are rolled from side to side,and are images widely taken containing right and left side portionregions of the fingers by rolling the fingers. That is, the rolled printimages include a total of ten images (ten kinds of rolled print images)that are two images of rolled prints of a thumb finger, an index finger,a middle finger, a ring finger and a little finger of both hands.

The slap print images are images taken containing fingertip region ofthe fingers by not rolling the fingers from side to side but standingthe fingers at front. The slap prints include: a thumb-finger slap (aslap print of a thumb finger) that a fingerprint of the thumb finger isindividually imprinted; and a four-finger slap (four kinds of slapprints) that fingerprints of the other four fingers (an index finger, amiddle finger, a ring finger and a little finger) are simultaneouslyimprinted. That is, the slap print images includes a total of fourimages that are two images of the thumb-finger slaps of the right andleft hands and two images of the four-finger slaps of the right and lefthands.

Accordingly, the tenprint card has the fourteen kinds of images and therolled prints of ten fingers and the slap prints of ten fingers areprinted in it.

In a non-patent literature 2 of “ANSI/NIST-ITL-1-2000 Data Format forthe Interchange of Fingerprint, Facial, & Scar Mark & Tattoo (SMT)Information” standardized in U.S. NIST (National Institute of Standardsand Technology), a rule for creating a digital image by scanning afingerprint image on the tenprint card is regulated.

This rule defines that fourteen individual images are created as digitalimages by segmenting the images along image frames on the tenprint card.

Furthermore, in this explanation, fingerprint images created as digitalimages with resolution of “500 ppi” are used based on this rule.

The slap print images are also used for checking a finger position error(an error of imprinting position) of the rolled prints by comparing theslap print images with the rolled print images.

The error of imprinting position is also called an error of imprintingsequence and this check is called a sequence check. The sequence checkexecuted by a computer has started from the 1990's. This starts withsegmenting individual fingers from the four-finger slap image.Segmenting the individual fingers from the four-finger slap is calledslap fingerprint segmentation or slap segmentation.

A non-patent literature 3 of “NISTIR 7209 Slap Fingerprint SegmentationEvaluation 2004 (SlapSeg04 Analysis Report)” issued by U.S. NISTdescribes accuracy and problems regarding the slap fingerprintsegmentation.

Recent fingerprint matching system is aimed at improving a hit rate of aleft fingerprint by registering not only ten fingers of the rolled printimages on the tenprint card but also ten fingers of the slap printimages in the database and using them as objects for left fingerprintmatching.

As described in the non-patent literature 1, appropriate fingerprintdetection is that fingerprints are imprinted completely inside the imageframes (the ruled line frames) printed on the tenprint card. However,since a criminal who is fingerprinted may be uncooperative for takingfingerprints, the taken fingerprint images may be protruded from theframes without appropriately imprinted inside the frames.

As a related art, a patent literature 1 (Japanese patent publicationJP-Heisei 07-168925A) discloses a tenprint card input device. Thetenprint card input device includes: a tenprint card image input sectioninputting image data of a tenprint card by an image scanner and so on; adata process section; an image storage section; a display device; apointing device; and a segmented fingerprint image output sectionoutputting fingerprint image data segmented in units of fingers. Asegmentation information input section of the data process sectionmemorizes the input tenprint card image data into the image storagesection, overlaps ten segmentation frames for specifying respectivesegmentation ranges with the tenprint card image to displays them on thedisplay device, and makes an operator input segmentation information foreach finger. A segmentation editor section segments fingerprint imagesof respective fingers from the tenprint card image data of the imagestorage section based on the segmentation information, and edits andoutputs the segmented fingerprint image.

In addition, a patent literature 2 (Japanese patent publicationJP2003-173445A) discloses a fingerprint matching method and device. Thisrelated technique extracts the area of a region as core line stability,the region containing no feature point which is composed of points thata ridge of a fingerprint pattern diverges and points that a ridge endsand the region including a predetermined attention point as a center ofthe region, and then uses the region for matching.

Furthermore, a patent literature 3 (Japanese patent publicationJP2004-078434A) discloses a striped pattern image appraising device anda striped pattern image. In this related technique, a feature point datamatching section creates information of pair feature points. A core linedata matching section creates information of core line points of asearch side and a file side which make a pair. An image deformationcorrection section corrects data of the file side and reducesdeformation of an image by using not only the information of the pairfeature points but also the information of the core line points making apair. An appraisive image edition display section outputs both of dataof the search side and the corrected data of the file side in order toeasily appraise the data. For example, the section overlaps the data ofthe search side with the corrected data of the file side and outputsthem.

Moreover, a patent literature 4 (Japanese patent publication JP2008-040693A) discloses a line noise removing device, a line noiseremoving method and a line noise removing program. This line noiseremoving device includes an image binarization section, a line noisecertainty factor calculation section, a line noise region determinationsection, a density conversion section and an image synthesis section.The image binarization section creates a binary image by binarizing aninput image. The line noise certainty factor calculation section createsa rotation image which the binary image is rotated for each of aplurality of rotation angles, calculates an edge feature value for eachregion continuing black pixels of each rotation image, and calculates aline noise certainty factor. The line noise region determination sectionselects a rotation angle candidate from the rotation angles, anddetermines a line noise region based on the line noise certainty factor,for the rotation image corresponding to each rotation angle candidate.The density conversion section creates a density conversion image byexecutes a local image enhancement on the region corresponding to theline noise region of the input image. The image synthesis sectioncreates a synthesis image by synthesizing the density conversion imageswhen a plurality of the rotation candidates is present.

CITATION LIST Patent Literature

-   [PTL 1] JP-Heisei 07-168925A-   [PTL 2] JP 2003-173445A-   [PTL 3] JP 2004-078434A-   [PTL 4] JP 2008-040693A

Non Patent Literature

-   [NPL 1] “The Science of Fingerprints” by John Edgar Hoover, US DOJ,    FBI; 1984, [online], [Searched on Apr. 5, 2011], Internet, (URL:    http://www.gutenberg.org/files/19022/19022-h/19022-h.htm)-   [NPL 2] “ANSI/NIST-ITL-1-2000 Data Format for the Interchange of    Fingerprint, Facial, & Scar Mark & Tattoo (SMT) Information”,    [online], [Searched on Apr. 5, 2011], Internet, (URL:    ftp://sequoyah.nist.gov/pub/nistinternalreports/sp500-245-a16.pdf)-   [NPL 3] “NISTIR 7209 Slap Fingerprint Segmentation Evaluation 2004    (SlapSeg04 Analysis Report)”, [online], [Searched on Apr. 5, 2011],    Internet (URL: http://www.nist.gov/itl/iad/ig/upload/ir_7209.pdf)

SUMMARY OF INVENTION

An object of the present invention is to provide a tenprint card inputdevice which automatically segments individual fingerprint images on thetenprint card.

A tenprint card input device according to the present invention,includes: an image inputting device configured to create a digital imageof a tenprint card and input it, the tenprint card being that ruled lineframes for imprinting fingerprints of rolled prints and slap prints arepreliminarily printed and rolled prints and slap prints are imprinted; adata processing device configured to automatically segment regions ofrolled print images in ruled line frames and regions of slap printimages including regions outside the ruled line frames from an image ofthe tenprint card, match the rolled print images against the slap printimages, and segment fingerprint images for outputting by using thematching result; and an image outputting device configured to output thefingerprint images for outputting together with finger positions of thefingerprint images for outputting.

A tenprint card input method according to the present invention is atenprint card input method executed by a computing machine and includes:creating a digital image of a tenprint card and inputting it, thetenprint card being that ruled line frames for imprinting fingerprintsof rolled prints and slap prints are preliminarily printed and rolledprints and slap prints are imprinted; automatically segmenting regionsof rolled print images in ruled line frames and regions of slap printimages including regions outside the ruled line frames from an image ofthe tenprint card, matching the rolled print images against the slapprint images, and segmenting fingerprint images for outputting by usingthe matching result; and outputting the fingerprint images foroutputting together with finger positions of the fingerprint images foroutputting.

A storage medium according to the present invention is a storage mediumincluding a program that, when executed, causes a computing machine toperform the following: creating a digital image of a tenprint card andinputting it, the tenprint card being that ruled line frames forimprinting fingerprints of rolled prints and slap prints arepreliminarily printed and rolled prints and slap prints are imprinted;automatically segmenting regions of rolled print images in ruled lineframes and regions of slap print images including regions outside theruled line frames from an image of the tenprint card, matching therolled print images against the slap print images, and segmentingfingerprint images for outputting by using the matching result; andoutputting the fingerprint images for outputting together with fingerpositions of the fingerprint images for outputting.

Consequently, appropriate fingerprint regions can be segmented from atenprint card, and an error of imprinting position and an error offinger position specification can be reduced. Therefore, fingerprintmatching accuracy can be improved.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a view showing a configuration example of a tenprint cardinput device according to the present invention;

FIG. 2 is a view showing a configuration example of a data processingdevice;

FIG. 3 is a flowchart showing an operation of a fingerprint imagesynthesis processing according to the present invention;

FIG. 4 is a view showing an example of a tenprint card;

FIG. 5A is a view showing a rolled print of a right index fingerimprinted on a tenprint card image;

FIG. 5B is a view showing a slap print of the right index fingerimprinted on the tenprint card image;

FIG. 6 is a view showing ruled line frames extracted from the tenprintcard;

FIG. 7 is a view showing an example of a ruled line frame superimposeddisplay on the tenprint card image;

FIG. 8A is a view showing an example of fourteen images of the tenprintcard after removing ruled line noise;

FIG. 8B is a view showing an example of an enlarged display of an imageof a small region surrounded by a broken line before ruled lines areremoved;

FIG. 8C is a view showing an example of an enlarged display of the imageof the small region surrounded by the broken line after the ruled linesare removed;

FIG. 9 is a view showing an example of images of rolled prints of tenfingers segmented for matching search;

FIG. 10A is a view showing an example of an image of slap prints of fourfingers of a left hand segmented for matching search;

FIG. 10B is a view showing an example of an image of a slap print of athumb finger of the left hand segmented for matching search;

FIG. 10C is a view showing an example of an image of slap prints of fourfingers of a right hand segmented for matching search;

FIG. 10D is a view showing an example of an image of a slap print of athumb finger of the right hand segmented for matching search;

FIG. 10E is a view showing an example of an image of slap prints of tenfingers segmented for matching search;

FIG. 11A is a view showing an example of an image of a rolled print of aright index finger for matching search;

FIG. 11B is a view showing an example of an image of slap prints of fourfingers of the right hand for matching search;

FIG. 12A is a view showing an example of an image of a rolled print(search side) of a right index finger for matching search;

FIG. 12B is a view showing an example of an image of a slap print(matching object side) of a right index finger for matching search;

FIG. 12C is a view showing an example of an image of a fingerprintregion of a slap print of aright index finger;

FIG. 13 is a view showing an example of an image of a rolled print (arolled print for outputting) of a left ring finger in which a part of aregion of a slap print is removed;

FIG. 14 is a view showing an example of images of rolled prints of tenfingers and slap prints of ten fingers for outputting;

FIG. 15 is a view showing an example of fourteen images which aredigital images created by a conventional technique;

FIG. 16 is a view showing an example of images of individualfingerprints (there are fingerprint regions extended beyond the frame)which are segmented from a four-finger slap of a right hand; and

FIG. 17 is a view showing an example of images of fingerprintimpressions of five fingers in a frame of a four-finger slap of a righthand.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Exemplary Embodiments

Exemplary embodiments of the present invention will be described belowreferring to the accompanying drawings.

[Tenprint Card Input Device]

A configuration example of the tenprint card input device according tothe present invention will be described with reference to FIG. 1.

The tenprint card input device according to the present inventionincludes an image inputting device 10, a data processing device 20 andan image outputting device 30.

The image inputting device 10 creates a digital image of the tenprintcard taken by a camera, a scanner and so on and inputs it. In addition,the image inputting device 10 can input the tenprint card which has beencreated as a digital image and received from an external storage deviceand so on through a network.

The data processing device 20 segments individual fingerprint imagesfrom the tenprint card and creates individual fingerprint images. Thedata processing device 20 is realized by a processor which is driven andexecutes a predetermined processing based on a program, a memory whichstores the program and various kinds of data and an interface (I/F) tothe outside.

The image outputting device 30 outputs the segmented individualfingerprint images (the individual fingerprint images) and informationof finger positions of the respective fingerprint images. The fingerposition indicates a kind of fingers such as a thumb finger, an indexfinger, a middle finger, a ring finger and a little finger.

[Data Processing Device]

A detail of the data processing device 20 will be described withreference to FIG. 2.

The data processing device 20 includes the data processing controllingsection 21, the data storing section 22, the frame ruled line extractingsection 23, the frame ruled line removing section 24, the rolled printsegmenting section 25, the slap print segmenting section 26, thefingerprint matching section 27, the corresponding common regionextracting section 28 and the corresponding relationship checkingsection 29.

The data processing controlling section 21 executes program control ofall configuration elements of the data processing device 20 and controlsthe interface to the outside. Here, the data processing controllingsection 21 controls internal configurations of the data processingdevice 20, the interface to the image inputting device 10 and theinterface to the image outputting section 13.

The data storing section 22 provides work areas to respective elementsof the data processing device 20 and temporarily stores data created bythe respective elements of the data processing device 20.

The frame ruled line extracting section 23 analyzes the inputted imageof the tenprint card and extracts ruled line frames for fourteen images.Here, the fourteen images are just one example.

The frame ruled line removing section 24 removes the ruled line framesfor the fourteen images.

The rolled print segmenting section 25 segments rolled print images often fingers. Here, the ten fingers are just one example.

The slap print segmenting section 26 segments slap print images of fourfingers for matching objects. Here, the four fingers are just oneexample.

The fingerprint matching section 27 individually matches the segmentedrolled print images of ten fingers for searching against the slap printimages for matching objects containing respective fingers. When findingregions similar to each other, the fingerprint matching section 27outputs corresponding point information together with a matching score.

The corresponding common region extracting section 28 extracts acorresponding common region by using the corresponding point informationas the matching result.

The corresponding relationship checking section 29 checks acorresponding relationship between the rolled prints and the slap printsand detects an error of imprinting position. In addition, thecorresponding relationship checking section 29 assesses the fingerpositions and detects an error of imprinting finger position. If thecorresponding relationship has inconsistency, there is possibility thatthe fingerprint imprinting position is wrong, and thus the correspondingrelationship checking section 29 outputs a warning message indicatingthat fact.

[Example of Hardware]

Example of concretely hardware for realizing the tenprint card inputdevice according to the present invention will be described below.

As an example of the image inputting device 10, a device which convertsvideo pictures into electric signals by using a semiconductor elementreacting to light like a CCD (Charge Coupled Device) and a CMOS(Complementary Metal Oxide Semiconductor) such as a scanner, a digitalcamera or a video camera is supposed. In addition, a cellular phone, asmart phone, a smart book, a car navigation system, a door phone, anintercom, a mobile game machine, a home video game machine, a mobilemusic player, a handy terminal, a gadget (an electric device), aninteractive television, a digital tuner, a digital recorder, aninformation home appliance, an OA (an office automation) device, an ATM(automated teller machine), a point-of-sales terminal, ahighly-functional copy machine, or a digital signage, which has a camerafunction, is also supposed. Furthermore, the image inputting device 10may be a device for reading various information transmitting medium andan interface for obtaining information from an external input device andstorage device.

As an example of the data processing device 20, a computing machine suchas a PC (a personal computer), an appliance, a thin client server, aworkstation, a main frame or a supercomputer is supposed. Here, the dataprocessing device 20 may be an extension board mounted on a computingmachine or may be a virtual machine (a VM) established on a physicalmachine.

As an example of the image outputting device 30, a display device suchas a LCD (a liquid crystal display), a PDP (a plasma display panel) oran organic EL display (an organic electroluminescence display), aprinting device which prints output contents on papers such as a printeror a projecting device which projects output contents on a wall or ascreen such as a projector is supposed. In addition, the imageoutputting device 30 may be the same device as the image input device10. Furthermore, the image output device 30 may be the interface foroutputting information to external display devices, storage devices andso on.

The data processing device 20 may be connected to the image inputtingdevice 10 and the image outputting device 30 through a network. As anexample of the network, the Internet, a LAN (a local area network), awireless LAN (a wireless local area network), a WAN (a wide areanetwork), a backbone, a cable television (a CATV) line, a fixed-linephone network, a cellular phone network, the WiMAX (the IEEE 802.16a),the 3G (the 3rd generation), a lease line, an IrDA (an infrared dataassociation, the Bluetooth (the registered trademark), a serialcommunication line or a data bus is considered.

Incidentally, the image inputting device 10, the data processing device20 and the image outputting device 30 may be mounted on a mobile objectsuch as a vehicle, a ship or an aircraft. The image inputting device 10,the data processing device 20 and the image outputting device 30 may beintegrated.

As an example of the data processing controlling section 21, a processoris supposed. As an example of the processor, a CPU (a central processingunit), a NP (a network processor), a microprocessor, a microcontrolleror a semiconductor integrated circuit (a LSI: large scale integration)having a dedicated function is considered.

As an example of the data storing section 22, a memory is supposed. Asan example of the memory, a semiconductor memory device such as a RAM (arandom access memory), a ROM (a read only memory), an EEPROM (anelectrically erasable and programmable read only memory) or a flashmemory, an auxiliary storage device such as a HDD (a hard disk drive) ora SSD (a solid state drive), or a storage medium such as a removabledisk like a DVD (a digital versatile disk) or a SD memory card (a securedigital memory card) is considered. A buffer or a register may also beused. Or, a storage device such as a DAS (a direct attached storage), aFC-SAN (a fibre channel-storage area network), a NAS (a network attachedstorage) or an IP-SAN (an IP-storage area network) may be used.

Incidentally, the above processor and the above memory may beintegrated. For example, recently, a microcomputer has been developingto be one chip. Accordingly, the case may be considered that one chipmicrocomputer mounted on an electric device includes both of the aboveprocessor and the above memory.

As examples of the frame ruled line extracting section 23, the frameruled line removing section 24, the rolled print segmenting section 25,the slap print segmenting section 26, the fingerprint matching section27, the corresponding common region extracting section 28 and thecorresponding relationship checking section 29, the above processor orthe combination of the above processor and the above memory is supposed.Here, each of the frame ruled line extracting section 23, the frameruled line removing section 24, the rolled print segmenting section 25,the slap print segmenting section 26, the fingerprint matching section27, the corresponding common region extracting section 28 and thecorresponding relationship checking section 29 may be a module, acomponent or a dedicated device, or a boot (a calling) program thereof.

However, practically, they are not limited to these examples.

[Fingerprint Image Synthesis Processing]

An operation flow of fingerprint image synthesis processing according tothe present invention will be described with reference to FIG. 3.

(1) Step S1

The image inputting device 10 inputs image data of a tenprint image as agrayscale image into the data processing device 20. The fingerprintimage data is digital data. The image inputting device 10 scans atenprint card to create the tenprint card image data. Or, the imageinputting device 10 reads the tenprint card image data stored in arecording medium such as a magnetic disk or an optical disk. At thistime, the data storing section 22 stores the tenprint card image data.FIG. 4 shows an example of the tenprint card image. The tenprint cardimage in FIG. 4 has fourteen ruled line frames for fingerprint images,and ten rolled prints and ten slap prints are imprinted. FIG. 5A shows arolled print of the right index finger imprinted on the tenprint cardimage of FIG. 4. FIG. 5B shows a slap print of the right index fingerimprinted on the tenprint card image of FIG. 4. Below, the case that thetenprint card input method is applied to the fingerprint image shown inFIG. 4 will be described.

(2) Step S2

The frame ruled line extracting section 23 analyzes the tenprint cardimage stored in the data storing section 22 and extracts the ruled lineframes for the fourteen images. The extraction of the ruled lines can beeasily realized by using a conventional technique. For example, it ispossible to calculate density accumulation values in a horizontaldirection and a vertical direction and detect peaks of the accumulationvalues. FIG. 6 shows the ruled line frames extracted from the tenprintcard of FIG. 4. In addition, the ruled lines corresponding to the ruledline frames for the fourteen images where the fingerprints are imprintedcan be easily assessed by analyzing a size and positional relationshipof the ruled line frames. FIG. 7 shows an example that the detectedruled line frames for the fourteen images are superimposed onto thetenprint card image.

(3) Step S3

The frame ruled line removing section 24 removes the ruled line framesfor the fourteen images. This removal of the ruled lines can be realizedby a conventional technique shown in the patent literature 4. FIG. 8Ashows a fingerprint image region of the tenprint card where the ruledlines are removed as described above. FIG. 8B shows an enlarged displayof an image of a small region surrounded by a broken line in FIG. 8Abefore the ruled lines are removed. FIG. 8C shows an enlarged display ofthe image of the small region surrounded by the broken line in FIG. 8A.That is, FIG. 8B shows the small region before the ruled lines areremoved and FIG. 8C shows the small region after the ruled lines areremoved. When FIG. 8C is compared with FIG. 8B, it is found that theruled lines are effectively removed and the fingerprint ridges becomeclear in FIG. 8C.

(4) Step S4

The rolled print segmenting section 25 segments the rolled prints of tenfingers. A method of segmenting a rolled print for matching searchaccording to the present invention is a simple method of clipping therolled print along the ruled line frame corresponding to each finger.This rolled print is used for a search side in matching with respect toa slap print. FIG. 9 shows images of the rolled prints of ten fingerssegmented for matching search.

(5) Step S5

The slap print segmenting section 26 segments the slap prints of fourimages used for matching objects. In the segmentation of slap printsused for matching objects, the slap print is segmented greater than theruled line frame (here, extended beyond the frame by 0.4 inches or 200pixels) and a portion protruded from (extended beyond) the frame is alsocontained in the slap print. FIGS. 10A to 10D show the slap prints offour images for matching objects segmented as described above. As shownin these figures, it is found that, since the slap print is segmentedgreater than the ruled line frame, the fingerprint region protruded fromthe frame is also contained in the slap print. In addition, instead ofsegmenting the slap prints of four images, for example, as shown in FIG.10E, a whole image of slap prints of ten fingers may be used for slapprints for matching objects. However, in this case, it takes long timefor matching as compared with matching using four regions, which is aweak point. Or, it may be considered that individual finger images aresegmented from the image of the four-finger slap. However, in this case,if the segmentation of the individual fingers from the four-finger slapgoes wrong, the expected matching result cannot be obtained, which is aweak point.

(6) Step S6

The fingerprint matching section 27 individually matches the segmentedrolled print images of ten fingers for searching against the slap printimages for matching objects in which respective fingers are contained.Here, by using feature point matching of a conventional technique shownin the non-patent literature 2 (JP 2003-173445A), the fingerprintmatching is performed. When finding regions similar to each other as aresult of the matching, the fingerprint matching section 27 outputscorresponding point information together with a matching score. Here,the corresponding point is a feature point pair judged that a featurepoint of the search side and a feature point of the matching object sidecorrespond to each other. For example, when the rolled print image ofthe right index finger shown in the example of FIG. 11A is used for thesearching side, the fingerprint matching section 27 matches it againstthe right four-finger slap image for matching objects shown in FIG. 10C.As a result, it is expected that a feature point is found on the slapprint image of the right index finger. Here, FIG. 11B is an enlargedimage of FIG. 10C.

(7) Step S7

The corresponding common region extracting section 28 extracts acorresponding common region by using the corresponding point informationas the matching result of the step S6. The corresponding common regionis determined as regions neighboring the corresponding points and aregion surrounded by the corresponding points. Or, a conventionaltechnique disclosed in the patent literature 3 (JP 2004-078434A) may beused. FIG. 12A shows the rolled print for the searching and FIG. 12Bshows the slap print corresponding to FIG. 12A which comes out from theresult of the matching. This slap print is rotated such that itsfingertip direction coincides with the fingertip direction of the rolledprint of FIG. 12A. At this time, the corresponding common regionextracting section 28 may rotate the slap print so as to adjust itsfingertip direction to the fingertip direction of the rolled print ofFIG. 12A as the slap print shown in FIG. 12B. FIGS. 12A and 12B show thecorresponding common regions of two images as regions with diagonallines surrounded by broken lines. These corresponding common regions areextracted by using a conventional technique as shown in the patentliterature 3 (JP 2004-078434A).

(8) Step S8

The slap print segmenting section 26 determines slap print regions foroutputting and segments slap prints of ten fingers for outputting. Theslap print region for outputting is determined by extending thecorresponding common region extracted at the step S7. However, in somecases, the extended region is connected to a fingerprint region ofanother finger. Therefore, when extending the corresponding commonregion, the slap print segmenting section 26 compares the extendedregion with fingerprint ridges inside the corresponding common region,and limits the extended region to a region where ridges are smoothlyconnected, that is, where continuity is high. In addition, the slapprint segmenting section 26 removes a corresponding common region ofanother finger which comes out based on the matching of a rolled printof the other finger. FIG. 12C shows the fingerprint region of the slapprint of the right index finger, which is determined as described above.As shown in FIG. 12C, the fingerprint region is segmented containing theridge region protruded from the ruled line frame.

By repeating the processings of the steps S4 to S8 for the rolled printsof ten fingers for searching, the segmentation regions of the rolledprint regions of ten fingers can be determined.

(9) Step S9

The rolled print segmenting section 25 segments rolled prints of tenfingers for outputting. This processing can be achieved by removing theimage region of the slap print segmented at the step S8 from the imageof the rolled print for searching segmented at the step S4. For example,when a fingertip region of a slap print of a right ring finger isimprinted in a frame of a rolled print of a left ring finger, if thisregion can be judged as a part of the slap print, this region is removedfrom the rolled fingerprint image. FIG. 13 shows the rolled print of theleft ring finger in which a part of the region of the slap print isremoved as described above. FIG. 14 shows the rolled prints of tenfingers and the slap prints often fingers segmented by theabove-described sequence of the processings. It is found that the slapprints are segmented containing the regions protruded from the frames.

(10) Step S10

The corresponding relationship checking section 29 checks acorresponding relationship between the rolled prints for outputting andthe slap prints for outputting and detects an error of imprintingposition. In addition, the corresponding relationship checking section29 assesses the finger positions and detects an error of imprintingfinger position. If the corresponding relationship has inconsistency,there is possibility that the imprinting position is wrong, and thus thecorresponding relationship checking section 29 outputs a warning messageindicating that fact. The detail of the corresponding relationship checkwill be described later.

(11) Step S11

The data processing controlling section 21 extracts the rolled prints often fingers and the slap prints of ten fingers segmented by theabove-described processings and the check result at the step S10 fromthe data storing section 22. Then, the data processing controllingsection 21 outputs them through the image outputting section 13 to theoutside and finishes the sequence of the processings.

[Corresponding Relationship Check]

Next, the detail of the corresponding relationship check at the step S10will be described.

For example, in the case of a right thumb finger, when a right thumbfinger rolled print is matched against a right thumb finger slap printimage for a matching object, if a corresponding common region is found(a corresponding common region is extracted), it is judged thatimprinting positions of both of the rolled print and the slap print arecorrect. If a corresponding common region is not found (a correspondingcommon region is not extracted) against the right thumb finger slapprint image, it is presumed that an imprinting position of any of therolled print and the slap print is wrong. Therefore, a warning messageindicating that fact is outputted to prompt an operator to check.

Before this warning message is outputted, it is considered that matchingis performed against a corresponding slap print image of an oppositeside hand (a reversed hand) as another implementation idea. When thereversed hand is used (in this case, when the right thumb finger rolledprint is matched against a left thumb finger slap print image for amatching object), if a corresponding common region is found, a warningmessage indicating that fact is outputted. Consequently, the check of anoperator can be easier.

In addition, for example, in the case of a right index finger to a rightlittle finger, when respective rolled prints are matched against a rightfour-finger slap image for matching objects, if corresponding commonregions are found and there is no inconsistency in a positionalrelationship of the corresponding common regions, it is judged thatimprinting positions of both of the rolled prints and the slap printsare correct.

Usually, in the positional relationship of the four-finger slap in theright hand, a corresponding common region of an index finger, acorresponding common region of a middle finger, a corresponding commonregion of an ring finger and a corresponding common region of a littlefinger are arranged in this order from a left side. Therefore, if thisrelationship does not hold, it can be judged that there is inconsistencyin the positional relationship.

If a corresponding common region is not found or there is inconsistencyin the positional relationship of the corresponding common regions, itis presumed that imprinting positions of any of the rolled prints andthe slap prints are wrong. Therefore, a warning message indicating thatfact is outputted to prompt an operator to check.

When there is inconsistency in the positional relationship of thecorresponding common regions, if the corresponding common region of atleast one of four fingers is found, it is judged that the imprintingpositions of the slap prints are correct and the imprinting positions ofthe rolled prints are wrong. However, if the corresponding commonregions of whole four fingers are not found, there is a possibility thatimprinting positions of the four-finger slap are wrong. For example,there is a possibility that the rolled prints and the slap prints arereversed hand.

Also, for the left five fingers, check as described above similar tothat for the right five fingers is performed.

CONCLUSION

As described above, the present invention provides, in a tenprint cardinput processing, a method of segmenting fingerprint regions ofrespective fingers from the tenprint card, and a method of detecting anerror of an imprinting position in high accuracy.

Specifically, the present invention provides, in a system executingcomputer-processing of a tenprint card where fingerprint images areimprinted, a processing mechanism for automatically segmenting therespective fingerprint images on the tenprint card.

Particularly, the present invention provides, even if a fingerprintimage of a slap print does not fit into a predetermined frame or even ifthere is noise other than a fingerprint which is an object forsegmentation inside a frame of a four-finger slap, a processingmechanism which can appropriately segment the slap print image by usinga matching result against a rolled print.

In addition, the present invention provides a processing mechanism whichchecks a corresponding relationship between rolled prints and slapprints, detects an error of imprinting position, assesses fingerpositions and detects an error of imprinting finger position.

As a result, the appropriate fingerprint regions can be segmented, andthe error of imprinting position and the error of imprinting fingerposition can be reduced. Thus, improvement of the accuracy of thefingerprint matching can be expected.

For example, when a tenprint card is inputted by using the conventionaltechnique, usually, images are segmented and their digital images arecreated according to frames for fourteen images.

FIG. 15 shows an example that the tenprint card of FIG. 4 is inputted byusing the conventional technique and fourteen images are created asdigital images.

There is a problem that, if a fingerprint is not imprinted appropriatelyinside the frame, a fingerprint region protruded from the frame isremoved. Specifically, regarding a four-finger slap, there are manyfingerprints protruded from the frame, the lack of the fingerprintregions is problem.

As shown in FIG. 15, it is found that, in the image of the four-fingerslap, the fingerprint regions protruded from the frames are removed.

Moreover, there is a problem that individual fingerprints cannot besegmented from the four-finger slap image if the slap prints are notappropriately imprinted in the frame.

Even if the individual fingerprints can be segmented from thefour-finger slap image, they are not perfect fingerprints. Therefore,there is a problem that matching against the rolled prints goes wrong,and consequently the check of the error of imprinting position goeswrong.

FIG. 16 shows an example that individual fingerprints are segmented fromthe right four-finger slap image. As shown in FIG. 16, it is found thatthe fingerprint regions protruded from the frame are lacked.

Furthermore, there is a problem that, if fingerprint impressions morethan five fingers inside the frame of the four-finger slap or if thereis noise on a paper base, four fingers cannot be segmentedappropriately.

FIG. 17 shows an example of fingerprint impressions of five fingersinside the frame of the four-finger slap. In this case, four fingerscannot be segmented appropriately, and consequently the check of theerror of imprinting position goes wrong.

Moreover, there is a problem that, even if the fingerprint can besegmented containing the region protruded from the frame by scanning theslap print largely beyond the frame ruled line, the ruled lines of theframe exists on the fingerprint ridges, and therefore, the matchingaccuracy is degraded.

In addition, an automatic processing technique that can appropriatelysegment the fingerprint image protruded from the frame is notestablished, an operator should manually specify the image, which makesoperation burden heavy.

Accordingly, the present invention provides a processing mechanism whichcan appropriately segment the slap print image by using a matchingresult against the rolled print even if there is a fingerprint regionprotruded from a frame in slap images of ten fingers imprinted on thetenprint card or even if there is noise other than a fingerprint whichis an object for segmentation inside a frame of a four-finger slapimage. In addition, the present invention provides a processingmechanism which effectively removes the ruled lines of the frame.Furthermore, the present invention provides a processing mechanism whichcan improve the accuracy of the fingerprint segmentation even if qualityof the four-finger slap image is low.

As a result, the appropriate segmentation of the fingerprint regions canbe achieved, and the error of imprinting position can be reduced.Therefore, the accuracy of the fingerprint matching can be improved.

The whole or part of the exemplary embodiments disclosed above can bedescribed as, but not limited to, the following supplementary notes.

(Supplementary Note 1)

A tenprint card input device includes:

a processing mechanism configured to segments a slap print image when arolled print is segmented from a tenprint card as a searching side, theslap print image being that a slap print whose finger position is thesame as the rolled print is imprinted, and the slap print image beingsegmented as a region externally greater than a ruled line frame by atleast 0.4 inches;

a processing mechanism configured to perform fingerprint matching of therolled print against the slap print as the slap print image as amatching object; and

a processing mechanism configured to segment a region continuing acorresponding common region determined based on a result of thefingerprint matching as a region of the corresponding slap print.

(Supplementary Note 2)

The tenprint card input device according to the supplementary note 1,further includes:

a processing mechanism configured to appropriately segment the slapprint image by matching the rolled print against the slap print even ifthere is noise other than a fingerprint which is an object forsegmentation inside a frame of a four-finger slap image.

(Supplementary Note 3)

The tenprint card input device according to the supplementary note 1,further includes:

a processing mechanism configured to remove the ruled line frame.

(Supplementary Note 4)

The tenprint card input device according to the supplementary note 1,further includes:

a processing mechanism configured to rotate, by using a difference of afingertip direction determined based on a result of the fingerprintmatching between the rolled print and the slap print, the slap printimage such that the fingertip direction coincides with that of therolled print and output the slap print image.

<Remark>

While the invention has been particularly shown and described withreference to exemplary embodiments thereof, the invention is not limitedto these exemplary embodiments. It is apparent that various changes inform and details may be made therein without departing from the spiritand scope of the present invention.

This application is based upon and claims the benefit of priority fromJapanese patent application No. JP 2011-094029, the disclosure of whichis incorporated herein in its entirety by reference.

What is claimed is:
 1. A device, comprising: a memory; and a processorcoupled to the memory, wherein the processor performs operations, theoperations comprising: reading a tenprint card image which includes aplurality of fingerprint patterns and ruled lines being frames of afingerprint imprint area and a next fingerprint imprint area; segmentinga portion of the tenprint card image into a fingerprint image, thefingerprint image including straddling fingerprint patterns straddlingbetween a part of the fingerprint imprint area and a part of the nextfingerprint imprint area; and outputting a digital image of thesegmented fingerprint image including the straddling fingerprintpatterns.
 2. The device of claim 1, wherein the fingerprint imageincludes a slap fingerprint image, and wherein the operations furthercomprise extracting from the tenprint card image a slap fingerprintimage of which a slap fingerprint pattern lies across two fingerprintimprint areas.
 3. The device of claim 1, the operations furthercomprising: extracting from the tenprint card image at least twofingerprint images which include a same part of the fingerprint imprintarea.
 4. The device of claim 1, the operations further comprisingdetecting the ruled lines in the segmented fingerprint image; andremoving the ruled lines overlapping the segmented fingerprint image. 5.The device of claim 1, the operations further comprising: detecting theruled lines in the segmented fingerprint image.
 6. The device of claim1, the operations further comprising: removing the ruled linesoverlapping the segmented fingerprint image.
 7. The device of claim 6,wherein, in the removing the ruled lines, fingerprint ridges becomeclear.
 8. The device of claim 6, wherein the removing the ruled linesincludes processing the segmented fingerprint image such thatfingerprint ridges become clear.
 9. The device of claim 1, wherein theprocessor outputs the digital image of the segmented fingerprint imageincluding the straddling fingerprint patterns to a display device. 10.The device of claim 1, wherein the processor outputs the digital imageof the segmented fingerprint image including the straddling fingerprintpatterns to one of a printer that prints contents of the digital imageof the segmented fingerprint image including the straddling fingerprintpatterns and a projector that projects the contents of the digital imageof the segmented fingerprint image including the straddling fingerprintpatterns.
 11. A method, comprising: reading a tenprint card image whichincludes a plurality of fingerprint patterns and ruled lines beingframes of a fingerprint imprint area and a next fingerprint imprintarea; segmenting a portion of the tenprint card image into a fingerprintimage, the fingerprint image including straddling fingerprint patternsstraddling between a part of the fingerprint imprint area and a part ofthe next fingerprint imprint area; and outputting a digital image of thesegmented fingerprint image including the straddling fingerprintpatterns.
 12. The method of claim 11, wherein the fingerprint imageincludes a slap fingerprint image, and wherein the method farthercomprises extracting from the tenprint card image a slap fingerprintimage of which a slap fingerprint pattern lies across two fingerprintimprint areas.
 13. The method of claim 11, further comprising:extracting from the tenprint card image at least two fingerprint imageswhich include a same part of the fingerprint imprint area.
 14. Themethod of claim 11, further comprising: detecting the ruled lines in thesegmented fingerprint image; and removing the ruled lines overlappingthe segmented fingerprint image.
 15. The method of claim 11, furthercomprising: detecting the ruled lines in the segmented fingerprintimage.
 16. The method of claim 11, further comprising: removing theruled lines overlapping the segmented fingerprint image.
 17. The methodof claim 11, wherein the outputting comprises sending the digital imageof the segmented fingerprint image including the straddling fingerprintpatterns to a display device.
 18. The method of claim 11, wherein theoutputting comprises sending the digital image of the segmentedfingerprint image including the straddling fingerprint patterns to aprinter to print contents of the digital image of the segmentedfingerprint image including the straddling fingerprint patterns.
 19. Themethod of claim 11, wherein the outputting comprises sending the digitalimage of the segmented fingerprint image including the straddlingfingerprint patterns to a projector to project contents of the digitalimage of the segmented fingerprint image including the straddlingfingerprint patterns.